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Trilogy Metals Announces Metallurgical, Geotechnical and Hydrogeological Results from the Arctic Deposit

Metallurgy & Processing

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News Release

Trilogy Metals Announces Metallurgical, Geotechnical and

Hydrogeological Results from the Arctic Deposit

April 19, 2017 - Vancouver, British Columbia – Trilogy Metals Inc. (TSX, NYSE-MKT:

TMQ) ("Trilogy Metals” or "the Company”) is pleased to announce the results of a recently

completed metallurgical test work program using sample material from the Arctic deposit

collected during the 2016 field season. This metallurgical test program was carried out as a

follow-on program to confirm previous metallurgical results completed in 2012 and in support

of advancing the project to a pre-feasibility study (“PFS”) planned for completion in Q1 2018.

Highlights – Recoveries and Concentrate Grades Improved from Previous Study

• Copper recoveries improved from 87% to 92%

• Zinc recoveries improved from 87% to 88%

• Copper concentrate average grade remains high at 29%

• Zinc concentrate average grade improves from 56% to 60%

• In-pit geotechnical and hydrology studies are now completed to a PFS level

The results demonstrate that excellent recoveries and clean concentrates of copper and zinc

can be generated from the polymetallic copper-lead-zinc-gold-silver ores at Arctic.

Concentrates of copper recovered an average of 91.7% of the copper and formed a concentrate

averaging 28.7% copper metal. Concentrates of zinc recovered an average of 87.8% of the zinc

and formed a concentrate averaging 60% zinc metal. Neither concentrate contains significant

deleterious penalty metals and are considered excellent quality by world standards. The lead

concentrate contains significant precious metals and is still undergoing further test work to

determine optimal recoveries for lead, gold and silver.

The Arctic deposit is a high-grade copper-zinc-lead volcanogenic massive sulfide deposit which

also contains significant amounts of precious metals. The Company is proposing a 10,000 tonne

per day, open pit mining operation with a typical crush-grind-float flow sheet producing

significant tonnages of copper and zinc concentrates and lessor lead concentrate containing

significant quantities of precious metals. The mineralized material from Arctic has been shown

to be amenable to traditional flotation methods for the production of saleable base-metal

concentrates. The results of this recent test work program, completed by ALS Metallurgy of

Kamloops, Canada, were in-line with previous results reported in the Company's National

Instrument 43-101 - Standards of Disclosure technical report entitled "Preliminary Economic

Assessment Report on the Arctic Project, Ambler Mining District, Northwest Alaska" dated

effective September 12, 2013 (the "PEA") (see press release dated September 12, 2013) and

will support a PFS to be completed in Q1, 2018.

TSX, NYSE-MKT

Symbol: TMQ

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Rick Van Nieuwenhuyse, President and CEO of Trilogy Metals commented, “We are very pleased

with the results of this metallurgical test work program at Arctic. Recoveries and concentrate

grades for our two principle metals – copper and zinc are excellent. We are currently conducting

additional test work to determine the optimal recoveries of our three other metals – lead, gold

and silver, and will report on that work in due course. In combination with recently completed

structural, hydrological and geotechnical work, we are well poised to kick-off the approved

2017 plan and budget and complete a PFS on Arctic in Q1 of 2018. The PFS will demonstrate the

true value of the high-grade Arctic deposit which we expect will be the first in a series of

potential mines in the Ambler mining district. With the recent announcement that the BLM has

initiated the permitting process on the AMDIAP, our recently announced option agreement with

South32 whereby they will fund a $10 million program at our Bornite deposit in 2017; and an

upswing in demand for copper and zinc, the Company is well positioned to add value for

shareholders by advancing development of the Ambler mining district.”

The revenue stream in the PEA (see figure 1 below) showed that copper produced 60% of the

revenue stream, with zinc contributing 21%, silver at 9% and gold at 6%. Lead was the least

valuable of the metals and is still undergoing further test work to determine optimal recoveries

for lead, gold and silver. Neither the zinc nor the copper concentrates contain any significant

deleterious penalty metals and are considered excellent quality by world standards.

Figure 1 – Revenue Stream from PEA

Copper, 60% Zinc, 21%

Lead, 4%

Gold, 6% Silver, 9%

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Metallurgical Update

A total of four diamond drill holes were completed during the 2016 field program to provide

whole core for sample materials in this test work program. Drilling targeted the first seven

years of planned mine production from the Arctic deposit and provided 14 major mineralized

intercepts for use in the test work program.

The metallurgical flow sheet envisions a truck and shovel open-pit mining operation followed by

a traditional crush-grind-float processing facility. Grinding test work completed on the 14

mineralized intercepts confirmed the material to be soft to moderate in terms of Bond Work

Index characterization. Bond Ball Mill work index averaged 7.6kWhr/tonne, with a maximum

value of 10.3 and minimum value of 5.3.

A composite sample of approximately 600 kilograms was prepared from the mineralized

intercepts and used for metallurgical concentration test work. This composite sample was used

in bench scale testing to confirm the performance of the previously defined flotation process; as

well, a large volume of the sample was processed in a pilot plant to provide sufficient volumes

of a copper-lead bulk concentrate to complete detailed copper and lead separation test work. A

flowsheet of the Arctic flotation process is shown in Figure 2.

Figure 2: Arctic Copper-Lead-Zinc Flowsheet Showing Talc Pre-Float

Metallurgical test work, as shown in Table 1, reflects good recovery and upgrading of copper,

lead and zinc values. The Arctic deposit contains talc, a naturally hydrophobic mineral. Talc is

recovered via flotation prior to base metals flotation. Copper and zinc losses associated with the

talc concentrate are less than one percent of the overall base metals. Copper and zinc

concentrates as defined in this test work program are considered to be excellent in terms of

concentrate grades. The lead concentrate which contains significant precious metals will be

subject to further economic analysis and possibly additional metallurgical testing for the

recovery of precious metals.

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Table 1: Arctic Deposit – Overall Metallurgical Performance (Bulk Sample)

Grades Metal Recoveries

Product Cu Pb Zn Au Ag Cu Pb Zn Au Ag

% % % g/t g/t % % % % %

Flotation Feed 3.13 0.93 4.75 0.61 46 100 100 100 - -

Pre-float Conc. 0.20 0.15 0.27 0.06 5 0.8 2.0 0.7 - -

Lead Conc. 2.72 23.8 1.32 7.12 933 2.4 76.9 0.9 63.4 59.4

Copper Conc. 28. 7 1.03 2.97 0.35 113 91.7 11.8 6.9 11.0 26.0

Zinc Conc. 0.79 0.24 60.0 0.44 24 1.8 1.8 87.8 - -

Final Tails 0.16 0.10 0.25 0.19 7 3.3 7.5 3.8 - -

Geotechnical & Hydrology Update

In spring of 2015, Trilogy Metals contracted SRK Consulting (Canada) Inc. to initiate open pit

geotechnical and hydrogeological field investigations to achieve prefeasibility level design for

the Arctic Project. SRK’s scope of work consisted of three broad phases, spanning two years of

staged technical investigations.

• Phase 1 focussed on data collection by means of a field investigation program tied to the

Arctic 2015 and 2016 exploration drilling programs. Geotechnical information collected

from the drilling programs included geotechnical rock mass classification data from

oriented drill core, testing of drill core for laboratory-derived rock properties, and

downhole acoustic and optical televiewer surveying. Hydrogeological testing included

packer testing, installation and monitoring of new and existing instrumentation within

the proposed open pit area, airlift testing and seepage surveys. As input for the

engineering studies, SRK also completed a structural geology study, and developed a

fault model based on field mapping, surface LiDAR data interpretation, drill hole logging

and a 3D geology model provided by Trilogy staff.

• Phase 2 undertook advanced geotechnical and hydrogeological characterization and

analyses, which resulted in the identification of six relevant geotechnical design sectors

for the planned open pit.

• Phase 3 included kinematic analyses, numerical modelling of representative pit sections

and derivation of overall, inter-ramp and bench scale slope design recommendations for

each geotechnical design sector.

Final inter-ramp angles per design sector vary depending on the slope direction within the

design sector, but in general are 26 to 56 degrees (see Figure 3). We are pleased to report that

SRK completed a final report documenting the structural, hydrological and geotechnical work in

February 2017 – this completes the work package to a Pre-feasibility level of study.

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Figure 3: Final Inter-ramp Angles Per Pit Slope Design Sectors (with 2013 PEA pit

shell for reference)

Qualified Persons

The metallurgical information in this news release has been prepared in accordance with

Canadian regulatory requirements set out in National Instrument 43-101 Standards of

Disclosure for Mineral Projects of the Canadian Securities Administrators ("NI 43-101") and

supervised and reviewed by Jeffrey B. Austin, P.Eng., President, of International Metallurgical

and Environmental Inc., a "Qualified Person" as defined in National Instrument 43-101 and the

person who oversees metallurgical developments for Trilogy Metals.

The 2015 and 2016 geotechnical and hydrological field investigations, technical analysis and

slope design recommendations were completed by Qualified Persons employed by SRK

Consulting (Canada) Inc. of Vancouver, Canada. Bruce Murphy P.Eng., Principal Consultant

with SRK, is a Qualified Person as defined by National Instrument 43-101. Mr. Murphy has

reviewed the geotechnical and hydrological technical information in this news release and

approves the disclosure contained herein.

About Trilogy Metals

Trilogy Metals Inc., formerly NovaCopper Inc., is a metals exploration company focused on

exploring and developing the Ambler mining district located in northwestern Alaska. It is one of

the richest and most-prospective known copper-dominant districts located in one of the safest

geopolitical jurisdictions in the world. It hosts world-class polymetallic VMS deposits that

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contain copper, zinc, lead, gold and silver, and carbonate replacement deposits which have

been found to host high grade copper mineralization. Exploration efforts have been focused on

two deposits in the Ambler mining district - the Arctic VMS deposit and the Bornite carbonate

replacement deposit. Both deposits are located within the Company's land package that spans

approximately 143,000 hectares. The Company has an agreement with NANA Regional

Corporation, Inc., a Regional Alaska Native Corporation that provides a framework for the

exploration and potential development of the Ambler mining district in cooperation with local

communities. Our vision is to develop the Ambler mining district into a premier North American

copper producer.

Company Contacts

Rick Van Nieuwenhuyse Elaine Sanders

President & Chief Executive Officer Vice President & Chief Financial Officer

[email protected] [email protected]

604-638-8088 or 1-855-638-8088

# # #

Cautionary Note Regarding Forward-Looking Statements

This press release includes certain "forward-looking information” and "forward-looking statements” (collectively

"forward-looking statements”) within the meaning of applicable Canadian and United States securities legislation

including the United States Private Securities Litigation Reform Act of 1995. All statements, other than statements of

historical fact, included herein, including, without limitation, statements relating to the potential timing and preparation

of a PFS on the Arctic deposit, the future operating or financial performance of the Company, planned expenditures and

the anticipated activity at the UKMP Projects, and anticipated activity with respect to the AMDIAP, are forward-looking

statements. Forward-looking statements are frequently, but not always, identified by words such as "expects”,

"anticipates”, "believes”, "intends”, "estimates”, "potential”, "possible”, and similar expressions, or statements that

events, conditions, or results "will”, "may”, "could”, or "should” occur or be achieved. These forward-looking

statements may include statements regarding perceived merit of properties; exploration plans and budgets; mineral

reserves and resource estimates; work programs; capital expenditures; timelines; strategic plans; market prices for

precious and base metals; or other statements that are not statements of fact. Forward-looking statements involve

various risks and uncertainties. There can be no assurance that such statements will prove to be accurate, and actual

results and future events could differ materially from those anticipated in such statements. Important factors that could

cause actual results to differ materially from the Company's expectations include the uncertainties involving the need

for additional financing to explore and develop properties and availability of financing in the debt and capital markets;

uncertainties involved in the interpretation of drilling results and geological tests and the estimation of reserves and

resources; the need for cooperation of government agencies and native groups in the development and operation of

properties as well as the construction of the access road; the need to obtain permits and governmental approvals; risks

of construction and mining projects such as accidents, equipment breakdowns, bad weather, non-compliance with

environmental and permit requirements, unanticipated variation in geological structures, metal grades or recovery

rates; unexpected cost increases, which could include significant increases in estimated capital and operating costs;

fluctuations in metal prices and currency exchange rates; and other risks and uncertainties disclosed in the Company’s

Annual Report on Form 10-K for the year ended November 30, 2016 filed with Canadian securities regulatory

authorities and with the United States Securities and Exchange Commission and in other Company reports and

documents filed with applicable securities regulatory authorities from time to time. The Company's forward-looking

statements reflect the beliefs, opinions and projections on the date the statements are made. The Company assumes

no obligation to update the forward-looking statements or beliefs, opinions, projections, or other factors, should they

change, except as required by law.

Cautionary Note to United States Investors

The Arctic Preliminary Economic Assessment and the Bornite Technical Report have been prepared in accordance with

the requirements of the securities laws in effect in Canada, which differ from the requirements of U.S. securities laws.

Unless otherwise indicated, all resource and reserve estimates included in this press release have been prepared in

accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects ("NI 43-101”) and the

Canadian Institute of Mining, Metallurgy, and Petroleum Definition Standards on Mineral Resources and Mineral

Reserves. NI 43-101 is a rule developed by the Canadian Securities Administrators which establishes standards for all

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public disclosure an issuer makes of scientific and technical information concerning mineral projects. Canadian

standards, including NI 43-101, differ significantly from the requirements of the United States Securities and Exchange

Commission ("SEC”), and resource and reserve information contained therein may not be comparable to similar

information disclosed by U.S. companies. In particular, and without limiting the generality of the foregoing, the term

"resource” does not equate to the term "reserves”. Under U.S. standards, mineralization may not be classified as a

"reserve” unless the determination has been made that the mineralization could be economically and legally produced

or extracted at the time the reserve determination is made. The SEC's disclosure standards normally do not permit the

inclusion of information concerning "measured mineral resources”, "indicated mineral resources” or "inferred mineral

resources” or other descriptions of the amount of mineralization in mineral deposits that do not constitute "reserves” by

U.S. standards in documents filed with the SEC. Investors are cautioned not to assume that any part or all of mineral

deposits in these categories will ever be converted into reserves. U.S. investors should also understand that "inferred

mineral resources” have a great amount of uncertainty as to their existence and great uncertainty as to their economic

and legal feasibility. It cannot be assumed that all or any part of an "inferred mineral resource” will ever be upgraded

to a higher category. Under Canadian rules, estimated "inferred mineral resources” may not form the basis of feasibility

or pre-feasibility studies except in rare cases. Investors are cautioned not to assume that all or any part of an "inferred

mineral resource” exists or is economically or legally mineable. Disclosure of "contained ounces” in a resource is

permitted disclosure under Canadian regulations; however, the SEC normally only permits issuers to report

mineralization that does not constitute "reserves” by SEC standards as in-place tonnage and grade without reference to

unit measures. The requirements of NI 43-101 for identification of "reserves” are also not the same as those of the SEC,

and reserves reported by the Company in compliance with NI 43-101 may not qualify as "reserves” under SEC

standards. Accordingly, information concerning mineral deposits set forth in this press release or the Bornite Technical

Report may not be comparable with information made public by companies that report in accordance with U.S.

standards.